Understanding RMS and Peak Wattage Figures on Sound systems

When choosing an Amplifier and Speakers, it is very easy to get mislead by confusing the many values, associated with power outputs. This short article aims to advise you on what figures to look at and which ignore.

RMS = Root Mean Square this is the industry standard method of measuring the output values associated with Power Outputs and also the MOST ACCURATE!!!.

Continuous = The continuous power which the item will handle for long periods of time. This is also an accurate way of determining the power handling of the product, and is much the same as RMS rating.

Program Power = Similar to RMS values and can be taken as being accurate figures.

Peak = This is the MAXIMUM power that a product can handle before damage occurs, and should NOT be used as an accurate measure of power.

PMPO = Peak Music Power Output, this again is a misleading figure and represents the maximum surge value that an item will withstand under ideal lab conditions before permanent damage occurs. PMPO figures are often exaggerated and should be ignored when making power comparisons.

To sum up:-

(1) When choosing an Amplifier and Loudspeakers, Pay attention only to the RMS, Continuous or Program Power Specifications.

(2) Always compare like for like comparisions. For instance correctly match the RMS power of an amplifier with the RMS Power of a Loudspeaker.

Never be tempted to match the Peak Power of a Speaker to the RMS Power of an Amplifier!.